In photography there is sometimes a need to make moving objects look all creamy and smooth. This is typical used for anything with water, like waterfalls, the sea, as well as people moving in a crowd for example, and there any many more scenarios where this technique can be used. And it can look very effective.
To do this we would need to slow down or restrict the amount of light coming into the lens, and at about 1/4 second is where this effect will start to occur.
Below are a couple of my images where I have used this effect to create calm and also a blurry effect of the clouds in the sky.
(More of my work can be found at www.be.net/richard-curtis)
To achieve this, especially in the day light we will make use of a filter. The filters will reduce the light by darkening down the scene by using stops. Such a filter is the 10 stop filter (the Lee Big stopper or Little Stopper being suitable candidates, however there are many similar ones on the market). You will also need a solid base, like a tripod to keep the camera still during the exposure.
For those that are not familiar with these types of filter, a big stopper filter looks like the following, and is placed in front of the lens. The Lee system required a bracket as the filters are lens independent, you can also get filters that screw on to the front of your lens.
and courtesy of Lee Filters, there is a time conversion chart when using either the Big or Little Stopper.
In Photography it’s pretty simple to get the effect. However, in video it’s not so easy. This is primarily because there isn’t the luxury of long exposures. Video is based on 25 or more frames per second and each frame lasts for 1/the frame rate. However, in the magical world of post production, there is quite a simple way of making this effect occur on video.
Take a look at this video that I shot in Iceland last year.
Here is the video with the long exposure applied
when you examine the video everything that was still will stay still and everything that moves will generate a blurred or long exposure effect (the same as in photography).
This effect was achieved by using the video timeline in Photoshop or Photoshop CC.
1. First of all you will need to open a video into Photoshop
You can also assemble video clips in Photoshop as well, or you may have used Premiere Pro to do this. In Photoshop, once the time line is open, you can click on the + icon to add more clips (marked in Red for video and yellow for audio).
2. You will need to turn the sound off from the track(s). You can do this by applying a right click to the timeline(marked in red below), then choosing the audio tab on the dialog that is displayed (marked in yellow), then turning the “mute audio” on (marked in pink).
Once you have the clip(s) loaded into Photoshop, you can then either trim them by dragging either the start or the end of each clip, or by applying the scissors at the play head.
3. If you are using multiple clips then you can convert the whole set of clips to a Smart Object (this will make the management of the next steps much easer). If there is just one clip then you have the choice of keeping as it is, or converting to the smart object. N.B by converting to a Smart Object you won’t be able to slow the motion down at the track level (this can be used this for creative effect for each track in the sequence, especially if 25fps is too fast).
To convert the clips to a Smart Object, select the clips that you would like to include, then right click on the layers (marked Red) or use the Layers panel flyout menu to select the ‘Convert to Smart Object” marked in pink.
The result will be a single layer (marked in red below), however, at any time you can double click on the Smart Object layer and edit the individual clips.
The next step is to create the long exposure,
1. Move the Smart Object layer outside of the Video Group by dragging the layer above the video group layer (marked Red)
2. Change the opacity of the Smart Object layer to be 10% (marked Orange)
3. Create a new layer beneath it that contains just black (marked Yellow). Make sure that the black layer is the same duration as the clip . You can do this by dragging the corresponding video layer within the timeline (marked yellow), then, if need by, adjusting the duration of the clip by dragging the end of the clip (marked blue).
Why do we need to do this? Essentially we will be duplicating the video clip 25 times more and each one will have a 10% opacity, which means the transparent background will show though, which will affect the playback. The black layer will give the opaque layers a background.
4. Duplicate the Smart object 25 times.
5. using the zoom in/out buttons (marked in red), zoom into the time line (the right hand side button). Zoom to the frame level (all of the way). The zoom will use the location of the playhead, so keep the playhead at the start of the time line.
6. Select all of the layers, except the first one and move them by one frame (see below).
7. Using the CMD (mac) / or CTRL (pc) key, deselect the top most layer of the recently moved set (in the example above number 44), then advance the group by one more frame. Repeat this until all 25 frames have been moved by one frame each (see below).
8. If you want to add some audio to the video, you can by selecting the audio track (marked in red) and adding an audio clip (marked in yellow). Remember we have turned off the audio for each track as 25 clips will create a noise, not music.
9. Export the video out of Photoshop using File / Export
Then play the resulting video.
There are many variables on this process that can be changed and worth experimenting with. I.e. the opacity of the layers and the frame duration (1frame). Feel free to experiment with different types of clips as well, not just water, but people moving in a city.
I would like to thank Gavin Hoey
(@Gavin_Hoey) for support during the making of this post, he was the one that made it all happen and worked out the final details. You can find more of Gavin’s work and tutorials here